(1) Field of the Invention
This invention relates to formulations of inoculum of microorganisms.
(2) Description of the Prior Art
New advances in biotechnology have focused on the production and delivery of bacterial and fungal biomass in formulations to be used as biological insecticides and herbicides (R. A. Doust, et al., 1983. Journal of Invertebrate Pathology 41:151-160; D. O. TeBeest and G. C. Templeton, 1985. Plant Disease 69:6-10; H. L. Walker and W. J. Connick, Jr., 1983. Weed Science 31:333-338). Similar technology with regard to production and delivery of biocontrol fungi effective against soilborne plant pathogens is almost nonexistent. The versatility, adaptability, and ease in handling species of fungi in the genera Trichoderma and Gliocladium has led to their effective use in biological control studies (G. C. Papavizas, 1985. Annual Review of Phytopathology 23: [Lin press]). However, the deficiencies in formulation technology are clearly an obstacle to the advancement of biological control research. Formulation of living, biocontrol propagules in alginate gel represents a breakthrough in biological control research. Recently, a procedure utilizing alginate gel formation to formulate spores of various biocontrol fungi and bacterial cells with a clay filler was described (D. R. Fravel, et al., 1985. Phytopathology 75:774-777.
Heretofore, various types of bulk organic matter, such as wheat bran, have been used to grow microorganisms. Non-granular formulations of fungi germinating on and colonizing bran have been applied loosely to soil to control certain plant diseases.
Connick, Jr., (U.S. Pat. Nos. 4,401,456 and 4,400,391) discloses processes for incorporating chemical, non-living, bioactive materials in alginate gels. Connick, Jr., (U.S. Pat. Nos. 4,401,456 and 4,400,391) discloses chemicals which are formulated to kill living matter. He also teaches the use of cations in the process, i. e. barium, copper, lead, zinc, all of which would be reasonably expected to kill any living fungi incorporated into the alginate gel.
The use of alginate gel technology to formulate agricultural products, pesticides and food items has also been disclosed. For example, U. S. Pat. No. 4,053,627 describes the use of alginate gel discs for mosquito control, U.S. Pat. No. 3,649,239 discloses fertilizer compositions, and U.S. Pat. No. 2,441,729 teaches the use of alginate gels as insecticidal as well as candy jellies. None of these patents discloses any method for incorporating living materials or fungi into an alginate gel matrix.